Type of works: supply and installation of replica lanterns for Battersea Bridge, using DW Windsor's Diamond Optic® reflector.
DW Windsor was approached by WSP and Transport for London (TfL) to refurbish the highly ornate columns and lanterns on Battersea Bridge.
The historical importance of the Bridge had to be recognised throughout the project along with consultation with English Heritage due to the declared Grade II status of the site (Battersea Bridge became a listed structure in 2008).
Improving upon the lighting levels was a must in addition to minimising the light spill onto the river and ensuring a high IP (Ingress Protection) rating to future-proof the fittings against the elements, ensuring life expectancy and illumination levels for years to come.
The challenges on this major project were three-fold. Firstly, the existing luminaires, fitted with a 70 watt High Pressure Sodium lamp in the main body of the luminaire and a 11watt PL Compact Fluorescent illuminating the top cap, (total energy consumption including circuit losses 94watts) were in a very poor condition, being both damaged and dirty. With loose and broken canopies the IP rating was extremely poor. Secondly, with many of the reflectors missing, light spill was quite dramatic, resulting in illumination of the River Thames and upward light in addition to incorrect levels of light where needed, on the carriageway and footways. Light pollution into the Thames had to be given careful consideration, as this could have caused problems with the clarity of the navigational lights (causing a possible distraction and hazard to the captains of the passing ships). Finally, refurbishing the columns on site, situated over the River Thames and on a bridge posed special complications.
DW Windsor recommended to the client that replicas of the lanterns be made, which would allow modern technology to be used, incorporating the Diamond Optic® reflector for optimum lighting control and energy efficiency. Replicas would automatically mean a vastly superior IP rating, as well as improved lighting performance. The use of this optic controlled the light spill onto the river and increased efficiency significantly.
The new luminaires, fitted with a 45watt White CosmoPolis lamp were designed to allow a small amount of light to filter upwards into the top of the luminaire, therefore negating the need for a lamp being installed especially for the top section.
The refurbishment of the existing columns on site was also a major aspect of the project. The complication of working over the River Thames tested the knowledge and experience of DW Windsor to the extreme. The refurbishment included shot-blasting, replacing and repairing a number of castings and re-coating the columns (in a PSX 700 FD which is a material that is extremely resilient to harsh environments and has an excellent track record in the marine industry).
To complete this work on the bridge, DW Windsor constructed bespoke structures to allow work to be undertaken safely and to create the correct conditions in which to carry out the refurbishment work to the highest possible standard.
The new lighting provided a 45% energy saving over the previous high pressure sodium scheme.
Senior Engineer, David O'Keefe of WSP UK commented: At WSP our vision is to be outstanding. Working towards achieving this vision is made so much easier with partners like DW Windsor. We were very impressed with the quality of the lighting products and the obvious pride that DW Windsors people took in installing them on our recent Battersea Bridge Relighting project funded and managed by Transport for London. We are confident that the excellent quality materials used and the exceptional workmanship involved in making the replicated lanterns will ensure lasting enjoyment to the public for many years to come. We look forward to working with DW Windsor again.